1 minute read
Problem 8. Stereoisomers of 1,2,3-Triphenylpropane-1,3-diol
8.1. Draw all possible stereoisomers of 1,2,3-triphenylpropane-1,3-diol.
Advertisement
8.2. List all the achiral compounds.
8.3. List all the chiral compounds.
8.4. Which of the following properties or methods can be used to distinguish between the chiral compounds from question 8.3? Choose all correct statements.
☐ boiling point ☐ UV spectroscopy ☐ refractive index ☐ melting point ☐ optical rotation ☐ dipole moment ☐ NMR spectroscopy in an achiral environment ☐ IR spectroscopy
Solution:
8.1. 1,2,3-Triphenylpropane-1,3-diol has an internal plane of symmetry. Therefore, the formula for the maximum number of stereoisomers 2n would give us 8 stereoisomers, but due to the fact that there is an internal plane of symmetry 1,2,3-triphenylpropane-1,3-diol exists as only four stereoisomers: two meso compounds and a pair of enantiomers. Carbon-2 in A and B is called a pseudo-asymmetric carbon atom. Carbon-2 in C and D is not a stereogenic center.
8.2.
8.3.
8.4.
☐ boiling point ☐ UV spectroscopy ☐ refractive index ☐ melting point ☒ optical rotation ☐ dipole moment ☐ NMR spectroscopy in an achiral environment ☐ IR spectroscopy
